The department uses a FBI database known as the Combined DNA Index System, better known as CODIS, to match biological evidence found at various crime scenes with the DNA profiles of people who have been convicted of previous crimes. Often, multiple crimes are not believed to be committed by the same suspect until the database is used to link the DNA.

According to Texas law, all felons, sex offenders and juveniles in the Texas Department of Criminal Justice and Texas Juvenile Justice Department systems are required to give a DNA sample.

“It would be difficult to overstate the impact of CODIS in law enforcement," DPS Director Steven McCraw said in a prepared statement. “Many of these crimes may never have been solved if not for this database." Officials say that roughly half of the suspects found with DNA matches were not incarcerated at the time, and all 10,000 of the matches are known as "cold hits," which the department considers "unexpected" matches of DNA profiles in the database to crime scene evidence.

The current database used by the department took effect in 1996, and since then, according to department officials, it has been used to analyze more than 660,000 DNA samples.

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